+ 1 on projection w/o adding or updating fields. IMO, the purpose is to split the record into something that is useful and something that is not.
Regards, Sandeep On Wed, Mar 9, 2016 at 9:08 PM, Chinmay Kolhatkar <[email protected]> wrote: > +1 for projection operator. > > @Sandesh, Adding of new fields and updating will be done as a part of > Enricher and Transform operator respectively. > I've sent another mail about Transform operator before. > > > On Wed, Mar 9, 2016 at 8:54 PM, Sandesh Hegde <[email protected]> > wrote: > > > +1 > > > > Adding of new fields and updating of fields can be part of this? > > > > On Wed, Mar 9, 2016, 5:50 AM Pradeep A. Dalvi <[email protected]> wrote: > > > > > Dear Folks, > > > > > > We are creating Projection Operator which will allow apex users to > > project > > > (select/drop) certain fields from the incoming tuples. This operation > > might > > > be done unconditionally or based on certain condition. > > > > > > Use case: > > > ------------- > > > Not all fields of tuples are of interest for the downstream operators. > In > > > such cases, one may want project selective fields to downstream. Also > one > > > may want to drop few fields, instead of selecting many. > > > In certain scenarios, one may want to project certain fields based on > > given > > > condition or expression. > > > > > > Functionality: > > > ----------------- > > > 1. Projection operator shall receive POJO as input tuple and emit 2 > POJOs > > > on separate output ports i.e. selected and dropped. Selected output > port > > > shall emit POJO with selected fields and dropped output shall emit POJO > > of > > > dropped fields. > > > 2. Operator needs select or drop fields as input params. This shall be > > > specified using comma separated list of fields. > > > 3. Operator shall emit POJO only on connected output ports. In another > > > words, if dropped output port is not connected, it shall not even try > to > > > generate POJOs with dropped fields. > > > > > > Please feel free to let me know your thoughts on this. > > > > > > Thanks, > > > Pradeep A. Dalvi > > > > > >
